N
Neil Shadrach
Ok I worked out an answer in the process of putting the question together so it's not desperate 
However a neater solution would be welcome if anyone has the enthusiasm.
#!/usr/bin/perl
use strict;
use warnings;
my $result;
foreach my $count (1..2)
{
my $s=qq(line $count goes first);
foreach my $p (qr/line . goes first/,qr/line (.) goes first/,qr/line (.) goes (\w+)/)
{
my @a;
print q(String="),$s,q(" Pattern="),$p,q(" Result=),$result++,q( match=),join(q),@a),q( $+=),defined $+?"def":"not","\
n" if @a=$s=~$p;
}
}
The above script produces the following results.
String="line 1 goes first" Pattern="(?-xism:line . goes first)" Result=0 match=1 $+=not
String="line 1 goes first" Pattern="(?-xism:line (.) goes first)" Result=1 match=1 $+=def
String="line 1 goes first" Pattern="(?-xism:line (.) goes (\w+))" Result=2 match=1:first $+=def
String="line 2 goes first" Pattern="(?-xism:line . goes first)" Result=3 match=1 $+=not
String="line 2 goes first" Pattern="(?-xism:line (.) goes first)" Result=4 match=2 $+=def
String="line 2 goes first" Pattern="(?-xism:line (.) goes (\w+))" Result=5 match=2:first $+=def
I want to discriminate between result 0 and result 1.
In the first case match equals 1 because the match succeeded while in the second case it equals 1 because
that happens to be the string matched by the first () - that is @a always has at least one value in the
event of a match with no parenthesis in the pattern or one pair both resulting in exactly one value.
I want to call a function in the event of a match with an array of the captured () values.
I could use (defined $+)?@a)) but I'm wondering if I could have arranged it such that @a was empty in
the result 0 case.
Thanks
However a neater solution would be welcome if anyone has the enthusiasm.
#!/usr/bin/perl
use strict;
use warnings;
my $result;
foreach my $count (1..2)
{
my $s=qq(line $count goes first);
foreach my $p (qr/line . goes first/,qr/line (.) goes first/,qr/line (.) goes (\w+)/)
{
my @a;
print q(String="),$s,q(" Pattern="),$p,q(" Result=),$result++,q( match=),join(q
),@a),q( $+=),defined $+?"def":"not","\n" if @a=$s=~$p;
}
}
The above script produces the following results.
String="line 1 goes first" Pattern="(?-xism:line . goes first)" Result=0 match=1 $+=not
String="line 1 goes first" Pattern="(?-xism:line (.) goes first)" Result=1 match=1 $+=def
String="line 1 goes first" Pattern="(?-xism:line (.) goes (\w+))" Result=2 match=1:first $+=def
String="line 2 goes first" Pattern="(?-xism:line . goes first)" Result=3 match=1 $+=not
String="line 2 goes first" Pattern="(?-xism:line (.) goes first)" Result=4 match=2 $+=def
String="line 2 goes first" Pattern="(?-xism:line (.) goes (\w+))" Result=5 match=2:first $+=def
I want to discriminate between result 0 and result 1.
In the first case match equals 1 because the match succeeded while in the second case it equals 1 because
that happens to be the string matched by the first () - that is @a always has at least one value in the
event of a match with no parenthesis in the pattern or one pair both resulting in exactly one value.
I want to call a function in the event of a match with an array of the captured () values.
I could use (defined $+)?@a
)) but I'm wondering if I could have arranged it such that @a was empty inthe result 0 case.
Thanks